DS78C20J National Semiconductor, DS78C20J Datasheet - Page 3

• Manufacturer Part Number: DS78C20J
• Description: IC LINE RX DUAL RS422/423 14CDIP
• Manufacturer: National Semiconductor
• Type: Line Receiverr

Specifications of DS78C20J

• Number Of Drivers/receivers: 2/0
• Protocol: RS232, RS422, RS423
• Voltage - Supply: 4.5 V ~ 15 V
• Mounting Type: Through Hole
• Package / Case: *
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *DS78C20J

t
t
t
t
pd0(D)
pd1(D)
pd0(S)
pd1(S)
Switching Characteristics
Note 2: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. Except for “Operating Temperature Range” they
are not meant to imply that the devices should be operated at these limits. The table of “Electrical Characteristics” provides conditions for actual device operation.
Note 3: Unless otherwise specified min/max limits apply across the −55˚C to +125˚C temperature range for the DS78C20 and across the 0˚C to +70˚C range for the
DS88C20. All typical values are for T
Note 4: All currents into device pins shown as positive, out of device pins as negative, all voltages referenced to ground unless otherwise noted. All values shown
as max or min on absolute value basis.
Note 5: Only one output at a time should be shorted.
Note 6: Refer to EIA-RS-422 for exact conditions.
V
Typical Applications
Note 7: (Optional internal termination resistor.)
a) Capacitor in series with internal line termination resistor, terminates the line and saves termination power. Exact value depends on line length.
b) Pin 1 connected to pin 2; terminates the line.
c) Pin 2 open; no internal line termination.
d) Transmission line may be terminated elsewhere or not at all.
Note 8: Optional to control response time.
Note 9: V
For signals which require fail-safe or have slow rise and fall times, use R1
and D1 as shown above. Otherwise, the positive input (pin 3 or 11) may be
connected to ground.
Symbol
CC
= 5V, T
CC
4.5V to 15V for the DS78C20. For further information on line drivers and line receivers, refer to applicaton notes AN-22, AN-83 and AN-108.
A
= 25˚C
Differential Input to “0” Output
Differential Input to “1” Output
Strobe Input to “0” Output
Strobe Input to “1” Output
A
Parameter
= 25˚C, V
CC
= 5V and V
RS-232-C Application with Hysteresis
DS005798-3
RS-422/RS-423 Application
CM
= 0V.
C
C
C
C
L
L
L
L
Conditions
3
= 50 pF
= 50 pF
= 50 pF
= 50 pF
Min
Typ
100
100
60
30
DS005798-4
DS005798-2
Max
100
150
150
70
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Units
ns
ns
ns
ns